The present invention relates to a magnetic recording and reproduction apparatus, and more particularly, to a magnetic recording and reproduction apparatus having a recording characteristic correction function, capable of recording a signal in an optimal recording condition by measuring characteristics of tape and head mechanism and adjusting a recording characteristic according to the measured characteristic.
It is usually difficult to record a video signal on tape directly in a magnetic recording and reproduction apparatus such as VCRs using magnetic tape as a recording medium. This is because a video signal has a frequency band of 30 Hz to 4.2 MHz. Thus, the video signal is modulated to alter a band of the video signal. Modulations methods include amplitude modulation (AM) and frequency modulation (FM). However, the FM method is chiefly used for recording a video signal on a recording medium.
Meanwhile, magnetic tape has a large characteristic deviation due to a difference of a magnetic force. According to the characteristic deviation, tape performance is determined. Tape is classified into standard (STD), high grade (HG), extra high grade (EHG), and a super VHS according to the performance. A head has a characteristic deviation equal to or more than approximately 30% according to its structure and magnetic material.
The magnetic characteristic of the magnetic tape also varies within the range which is specified under the standard of the magnetic recording and reproduction apparatus. Therefore, although a recording characteristic of the magnetic recording and reproduction apparatus is set based on tape having a standardized characteristic, it has been difficult to record a video signal fully reflecting the characteristic of the tape.
There have been various attempts to change a record characteristic based on the characteristics of a tape to be used. Among them, a method for obtaining an optimal recording current for every tape so that a reproduction level of a carrier is maximized is well-known. There is also a method for obtaining an optimal recording current at each frequency of a high-band, an intermediate-band, and a low-band.
To solve the above problems, it is an object of the present invention to provide a magnetic recording and reproduction apparatus having a recording characteristic correction function so that a signal can be recorded in an optimal recording condition, in which characteristics of tape and head mechanism to be used are measured and a record characteristic is corrected according to the measured characteristics.
To accomplish the above object of the present invention, there is provided a magnetic recording and reproduction apparatus using magnetic tape as a recording medium, the magnetic recording and reproduction apparatus comprising:
a test signal generator for generating a test signal to measure characteristics of tape and head mechanism; a recorder for modulating the test signal generated in the test signal generator and recording the modulated signal on the tape; a reproducer for reproducing the test signal which is modulated and recorded on the tape by the recorder; and an arithmetic control unit for estimating the characteristics of the tape and the head mechanism using the output from the reproducer, and correcting the recording characteristic of the recorder according to the estimated result.